Systems and methods for processing time-division signals and frequency-division signals

ABSTRACT

System and methods are provided for processing time-division signals and frequency-division signals using a multi-mode transceiver. The example system includes a power amplifier, a switching component, and a duplexer. The power amplifier is configured to receive a first time-division signal from the transceiver and to generate an amplified time-division signal based on the first time-division signal if the transceiver is in a time-division mode. The power amplifier is further configured to receive a first frequency-division signal from the transceiver and to generate an amplified frequency-division signal based on the first frequency-division signal if the transceiver is in a frequency-division mode. The switching component is configured to receive the amplified time-division signal from the power amplifier, and to output the amplified time-division signal for transmission. The duplexer configured to receive the amplified frequency-division signal from the switching component, and to output a transmission signal for transmission.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefit from U.S. ProvisionalPatent Application No. 61/486,705, filed on May 16, 2011, and entitled“Methods to reuse the WCDMA Band1 TX for TDSCDMA Band1/2,” the entiretyof which is incorporated herein by reference.

FIELD

The technology described in this patent document relates generally tomobile communication. More particularly, systems and methods aredisclosed for radio frequency signals processing.

BACKGROUND

Various technical standards are used for sending and receiving radiofrequency signals, such as Code Division Multiple Access (CDMA), GlobalSystem for Mobile Communication (GSM), Enhanced Data for GSM Environment(EDGE), CDMA-2000, Time Division Synchronous Code Division MultipleAccess (TDSCDMA), Wideband Code Division Multiple Access (WCDMA), LongTerm Evolution (LTE), and Worldwide Interoperability for MicrowaveAccess (WiMAX).

For example, WCDMA is a widely adopted third-generation (3G) airinterface standard. WCDMA supports a Frequency Division Duplex (FDD)mode of operation in which uplink communication (e.g., from a mobiledevice to a base station) and downlink communication (e.g., from a basestation to a mobile device) are carried out on two separate 5 MHzchannels. WCDMA includes a number of frequency bands, such as Band 1which covers 1920 MHz-1980 MHz and 2110 MHz-2170 MHz. The frequencyrange 1920 MHz-1980 MHz is used for uplink transmission, and thefrequency range 2110 MHz-2170 MHz is used for downlink transmission.

TDSCDMA is another 3G air interface standard that implements a TimeDivision Duplex (TDD) mode of operation in which a same channel is usedfor both uplink and downlink transmission, and a number of timeslots aredynamically assigned for downlink and uplink transmission. TDSCDMAincludes a number of frequency bands, such as Band 1 covering 2010MHz-2025 MHz, and Band 2 covering 1880 MHz-1920 MHz.

Different areas of the world rely on different technical standards forproviding radio frequency communication (e.g., cell phones, beepers,computers, etc.). To enable continual operation of consumer devices thatuse different standards, multi-mode devices may be provided forcommunication using each of a number of different standards that may beencountered. For example, dual-mode or tri-mode transceivers areavailable to transmit/receive WCDMA Band 1 signals and TDSCDMA Band 1/2signals within a single device. However, communication systemsconstructed based on the dual-mode or tri-mode transceivers usuallyinclude multiple power amplifiers, each being designed specifically fora particular frequency band, or an expensive multi-band multi-mode poweramplifier. Additionally, the communication system using the dual-mode ortri-mode transceiver usually includes a number of duplexers and filters,each having a particular bandwidth.

SUMMARY

In accordance with the teachings described herein, systems and methodsare provided for processing time-division signals and frequency-divisionsignals using a multi-mode transceiver. An example system may include apower amplifier, a switching component, and a duplexer. The poweramplifier is configured to receive a first time-division signal from thetransceiver and to generate an amplified time-division signal based onthe first time-division signal if the transceiver is in a time-divisionmode, the power amplifier being further configured to receive a firstfrequency-division signal from the transceiver and to generate anamplified frequency-division signal based on the firstfrequency-division signal if the transceiver is in a frequency-divisionmode. The first time-division signal is associated with a firstfrequency band, the first frequency-division signal being associatedwith a second frequency band. Additionally, the first frequency band isadjacent to the second frequency band. The power amplifier has abandwidth including the first frequency band and the second frequencyband. Further, the switching component is configured to receive theamplified time-division signal from the power amplifier and to outputthe amplified time-division signal for transmission, the switchingcomponent being further configured to receive the amplifiedfrequency-division signal from the power amplifier, and to output theamplified frequency-division signal for further processing. Furthermore,the duplexer is configured to receive the amplified frequency-divisionsignal from the switching component and to output a transmission signalfor transmission, the transmission signal being generated based on theamplified frequency-division signal.

As another example, a system for processing time-division signals andfrequency-division signals using a multi-mode transceiver may include apower amplifier, a switching component, and a duplexer. The poweramplifier is configured to receive a first time-division signal from thetransceiver and to generate an amplified time-division signal based onthe first time-division signal if the transceiver is in a time-divisionmode, the power amplifier being further configured to receive a firstfrequency-division signal from the transceiver and to generate anamplified frequency-division signal based on the firstfrequency-division signal if the transceiver is in a frequency-divisionmode. The first time-division signal is associated with a firstfrequency band, the first frequency-division signal being associatedwith a second frequency band, the first frequency band being adjacent tothe second frequency band, the power amplifier having a bandwidthincluding the first frequency band and the second frequency band. Theswitching component is configured to receive the amplified time-divisionsignal or the amplified frequency-division signal, and output theamplified time-division signal or the amplified frequency-divisionsignal for further processing. Additionally, the duplexer is configuredto receive the amplified time-division signal or the amplifiedfrequency-division signal from the switching component, and to output afirst transmission signal generated based on the amplified time-divisionsignal or a second transmission signal generated based on the amplifiedfrequency-division signal to an antenna switch circuit for transmission.The duplexer is further configured to receive a second time-divisionsignal from the antenna switch circuit, and to output a reception signalto the switching component, the reception signal being generated basedon the second time-division signal, the duplexer having a bandwidthincluding the first frequency band and the second frequency band.Furthermore, the switching component is further configured to receivethe reception signal and to output the reception signal to thetransceiver.

As another example, a method is provided for processing time-divisionsignals and frequency-division signals using a multi-mode transceiver.If the transceiver is in a time-division mode, a time-division signal isreceived at a power amplifier from the transceiver, the time-divisionsignal being associated with a first frequency band. An amplifiedtime-division signal is generated based on the time-division signal. Theamplified time-division signal is output for transmission. If thetransceiver is in a frequency-division mode, a frequency-division signalis received at a power amplifier from the transceiver, thefrequency-division signal being associated with a second frequency band,the first frequency band being adjacent to the second frequency band,the power amplifier having a bandwidth including the first frequencyband and the second frequency band. Additionally, an amplifiedfrequency-division signal is generated based on the frequency-divisionsignal. A transmission signal is generated based on the amplifiedfrequency-division signal at a duplexer. Furthermore, the transmissionsignal is output for transmission.

As another example, a method is provided for processing time-divisionsignals and frequency-division signals using a multi-mode transceiver.If the transceiver is in a time-division mode, a time-division signal isreceived at a power amplifier from the transceiver when the transceiveris in a transmission mode, the first time-division signal beingassociated with a first frequency band. An amplified time-divisionsignal is generated based on the first time-division signal. A firsttransmission signal is generated based on the amplified time-divisionsignal at a duplexer, the duplexer having a bandwidth including thefirst frequency band and a second frequency band, the first frequencyband being adjacent to the second frequency band. The first transmissionsignal is output to an antenna switch circuit for transmission. When thetransceiver is in a reception mode, a second time-division signal isreceived from the antenna switch circuit. A reception signal isgenerated based on the second time-division signal at the duplexer. Thereception signal is output to the transceiver. If the transceiver is ina frequency-division mode, a frequency-division signal is received atthe power amplifier from the transceiver, the frequency-division signalbeing associated with the second frequency band, the power amplifierhaving a bandwidth including the first frequency band and the secondfrequency band. An amplified frequency-division signal is generatedbased on the frequency-division signal. Furthermore, a secondtransmission signal is generated based on the amplifiedfrequency-division signal at the duplexer. The second transmissionsignal is output to the antenna switch circuit for transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a diagram of a conventionalcommunication system for processing WCDMA Band 1 signals.

FIG. 2 illustrates an example of a diagram of a conventionalcommunication system for processing TDSCDMA signals.

FIG. 3 illustrates an example of a diagram of a communication system forprocessing WCDMA Band 1 signals using a duplexer and processing TDSCDMABand 1/2 signals where the duplexer is bypassed.

FIG. 4 illustrates an example of a diagram showing frequency coverage ofa special duplexer that may be utilized for a communication system usinga multi-mode transceiver.

FIG. 5 illustrates an example of a diagram of a communication system forprocessing WCDMA Band 1 signals and TDSCDMA Band 1/2 signals using aspecial duplexer.

FIG. 6 illustrates an example flow diagram depicting a method forprocessing frequency-division signals in a frequency-division mode usinga duplexer and processing time-division signals in a time-division modewhere the duplexer is bypassed.

FIG. 7 illustrates an example flow diagram depicting a method forprocessing time-division signals in a time-division mode andfrequency-division signals in a frequency-division mode using a specialduplexer.

FIG. 8 illustrates an exemplary implementation of processingtime-division signals and frequency-division signals.

DETAILED DESCRIPTION

FIG. 1 illustrates an example of a diagram of a conventionalcommunication system 100 for processing WCDMA Band 1 signals. A WCDMABand 1 power amplifier 104 amplifies WCDMA signals 112 received from aWCDMA transceiver 102. A duplexer 106 receives amplified WCDMA signals114 from the power amplifier 104 and outputs transmission signals 116 toan antenna switch 108. Simultaneously, the duplexer 106 can receiveWCDMA signals 118 from an antenna switch 108 and output receptionsignals 120 to the transceiver 102.

FIG. 2 illustrates an example of a diagram of a conventionalcommunication system 200 for processing TDSCDMA signals. A TDSCDMA Band1/2 power amplifier 204 amplifies TDSCDMA Band 1/2 signals 214 receivedfrom a TDSCDMA transceiver 202. An antenna switch 210 receives amplifiedTDSCDMA Band 1/2 signals 216 for transmission. At a different time, theantenna switch 210 routes TDSCDMA Band 1 signals 218 received from anantenna 212 to a Band 1 filter 206, and alternatively routes TDSCDMABand 2 signals 220 received from the antenna 212 to a Band 2 filter 208.The outputs of the filters 206 and 208 are then transmitted to thetransceiver 202.

Certain synergies can be realized when consideration is given to theindividual components of the separate conventional systems shown inFIGS. 1 and 2. For example, a WCDMA Band 1 power amplifier (e.g., thepower amplifier 104 shown in FIG. 1) often has a bandwidth that coversmore than the WCDMA Band 1 uplink frequency range. Thus, the WCDMA Band1 power amplifier can often process, with satisfactory performance, theTDSCDMA Band 1/2 signals because the TDSCDMA Band 1 (2010 MHz-2025 MHz)and the TDSCDMA Band 2 (1880 MHz-1920 MHz) are adjacent to the WCDMABand 1 uplink frequency range (1920 MHz-1980 MHz). Similarly, a TDSCDMABand 1/2 power amplifier (e.g., the power amplifier 204 shown in FIG. 2)has a bandwidth that covers both the TDSCDMA Band 1 and the TDSCDMA Band2. Because the WCDMA Band 1 uplink frequency range is located betweenthe TDSCDMA Band 1 and the TDSCDMA Band 2, the WCDMA Band 1 uplinkfrequency range is usually within the bandwidth of a TDSCDMA poweramplifier so that the TDSCDMA power amplifier can process the WCDMA Band1 uplink signals. Thus, a single power amplifier, either the WCDMA Band1 power amplifier or the TDSCDMA Band 1/2 power amplifier, can be usedfor a communication system to process both the WCDMA Band 1 uplinksignals and the TDSCDMA Band 1/2 signals.

Another synergy can be realized when considering duplexers. As shown inFIG. 1, for processing the WCDMA Band 1 signals, a communication systemoften needs the duplexer 106 to isolate two different channels usedseparately for the WCDMA Band 1 uplink communication and downlinkcommunication. However, as shown in FIG. 2, a duplexer is not needed forprocessing the TDSCDMA Band 1/2 signals because a same channel is usedfor both the TDSCDMA uplink communication and the TDSCDMA downlinkcommunication. When a multi-mode transceiver is used for processing boththe WCDMA Band 1 signals and the TDSCDMA Band 1/2 signals, someconventional communication systems may force the TDSCDMA signals to passthrough a duplexer that is only necessary for the WCDMA signals. If theTDSCDMA Band 1/2 signals share a regular duplexer with the WCDMA Band 1signals, an insertion loss may be caused in the TDSCDMA Band 1/2signals.

To take advantage of these observations, a communication system forprocessing both WCDMA Band 1 signals and TDSCDMA Band 1/2 signals can beconstructed using a single power amplifier for both signals and aduplexer only for the WCDMA Band 1 signals, as shown in FIG. 3. FIG. 3illustrates an example of a diagram of a communication system 300 forprocessing WCDMA Band 1 signals using a duplexer and processing TDSCDMABand 1/2 signals where the duplexer is bypassed. The system 300 includesa transceiver chip 301 and an antenna 316. As shown in FIG. 3, the WCDMABand 1 uplink signals and the TDSCDMA Band 1/2 signals provided by amulti-mode transceiver 302 are amplified by a common power amplifier 304on the transceiver chip 301. A switch 306 routes the amplified WCDMAsignals to a duplexer 308, while the amplified TDSCDMA signals bypassthe duplexer 308 via the switch 306.

Specifically, when the communication system 300 is in a transmissionmode, signals are transmitted from the transceiver 302 to the antennaswitch 314. If the transceiver 302 is configured to output a TDSCDMABand 1/2 signal 318, then the power amplifier 304 amplifies the signal318, and the switch 306 routes the amplified TDSCDMA signal 320 to anantenna switch 314 for transmission. If the transceiver 302 isconfigured to output a WCDMA Band 1 uplink signal 330, the poweramplifier 304 amplifies the signal 330, the switch 306 routes anamplified WCDMA signal 332 to the duplexer 308, and the duplexer 308outputs a transmission signal 334 to the antenna switch 314 fortransmission.

When the system 300 is in a reception mode, signals are transmitted fromthe antenna switch 314 to the transceiver 302. When the antenna 316receives a TDSCDMA Band 1 signal 322, the antenna switch 314 routes thesignal 322 to a TDSCDMA Band 1 filter 310 that outputs a filtered signal326 to the transceiver 302. If the antenna 316 receives a TDSCDMA Band 2signal 324, the antenna switch 314 routes the signal 324 to the TDSCDMABand 2 filter 312 that in turn outputs a filtered signal 328 to thetransceiver 302. When the antenna 316 receives a WCDMA Band 1 downlinksignal 336, the antenna switch 314 routes the signal 336 to the duplexer308, which outputs a reception signal 338 to the transceiver 302.

As discussed above, the power amplifier 304 can be a WCDMA Band 1 poweramplifier, or a TDSCDMA Band 1/2 power amplifier. However, any otherpower amplifiers with a bandwidth that covers the WCDMA Band 1 uplinkfrequency range, the TDSCDMA Band 1 and the TDSCDMA Band 2 may beutilized as well.

The depicted system 300 supports both TDSCDMA and WCDMA transmissions.In addition, the transceiver 302 may support one or more of thefollowing air interface standards: CDMA, GSM, EDGE, CDMA-2000, LTE, andWiMax.

The system 300 may be varied in a number of ways while still offeringsatisfactory performance. For example, the switch 306 may be a singlepole, double throw (SPDT) switch. The antenna switch 314 may be a singlepole, multi-throw switch. The filters 310 and 312 may be surfaceacoustic wave (SAW) filters. Other variations are also contemplated asbeing within the scope of this disclosure.

FIG. 4 illustrates an example of a diagram showing frequency coverage ofa special duplexer that may be utilized for a communication system usinga multi-mode transceiver. As noted previously with respect to FIG. 3,the TDSCDMA signals can bypass the duplexer 306 to avoid insertion loss.Such loss results from conventional duplexers having a bandwidth (asshown at 402) which does not cover the TDSCDMA Band1/2. A specialduplexer can be constructed to have an extended bandwidth cover theWCDMA Band 1, the TDSCDMA Band 1, and the TDSCDMA Band 2, as shown at404. Such a special duplexer can be used to process the TDSCDMA Band 1/2signals without significant insertion loss. Thus, a communication systemcan be constructed using the special duplexer to further simplify systemstructure, as shown in FIG. 5.

FIG. 5 illustrates an example of a diagram of a communication system 500for processing WCDMA Band 1 signals and TDSCDMA Band 1/2 signals using aspecial duplexer. The system 500 includes a transceiver chip 501 and anantenna 512. As shown in FIG. 5, a special duplexer 508 with an extendedbandwidth is used for processing both the WCDMA Band 1 signals and theTDSCDMA Band 1/2 signals.

When the system 500 is in a transmission mode, signals are transmittedfrom a multi-mode transceiver 502 to an antenna switch 510. Thetransceiver 502 outputs a signal 514 (e.g., a TDSCDMA Band 1/2 signal ora WCDMA Band 1 uplink signal) to a power amplifier 504. A switch 506receives an amplified signal 516 and outputs a signal 517 to the specialduplexer 508 (e.g., at a transmission port 509 of the special duplexer508). Then the special duplexer 508 outputs a transmission signal 518 tothe antenna switch 510 for transmission.

When the system 500 is in a reception mode, signals are transmitted fromthe antenna switch 510 to the transceiver 502. When the antenna 512receives a TDSCDMA Band 1/2 signal 520, the antenna switch 510 routesthe signal 520 to the special duplexer 508, and the special duplexer 508outputs a signal 521 (e.g., through the transmission port 509) to theswitch 506, which then outputs a signal 522 to the transceiver 502. Whenthe antenna 512 receives a WCDMA Band 1 downlink signal 524, the antennaswitch 510 routes the signal 524 to the special duplexer 508, and thespecial duplexer 508 outputs a reception signal 526 (e.g., through areception port 511 of the duplexer 508) to the transceiver 502.

For example, the power amplifier 504 can be a WCDMA Band 1 poweramplifier, or a TDSCDMA Band 1/2 power amplifier. However, any otherpower amplifiers with a bandwidth that covers the WCDMA Band 1 uplinkfrequency range, the TDSCDMA Band 1 and the TDSCDMA Band 2 may beutilized as well.

FIG. 6 illustrates an example flow diagram depicting a method forprocessing frequency-division signals in a frequency-division mode usinga duplexer and processing time-division signals in a time-division modewhere the duplexer is bypassed. At 602, a determination is made as towhether the transceiver is in a time-division mode or afrequency-division mode. When the transceiver is in the time-divisionmode, a determination is made as to whether the transceiver is in atransmission mode or a reception mode at 604. When the transceiver is inthe transmission mode, a first time-division signal (e.g., a TDSCDMABand 1/2 signal) is received at a power amplifier from the transceiverat 606. The first time-division signal is associated with a firstfrequency band (e.g., the TDSCDMA Band 1 and Band 2). An amplifiedtime-division signal is generated based on the time-division signal at608, and the amplified time-division signal is output to an antennaswitch circuit for transmission at 610. When the transceiver is in thereception mode, a second time-division signal (e.g., a TDSCDMA Band 1/2signal) is received from the antenna switch circuit at 612. The secondtime-division signal is associated with the first frequency band. Afirst reception signal is generated at a filter based on the secondtime-division signal at 614, and output to the transceiver at 616. Forexample, if the second time-division signal is a TDSCDMA Band 1 signal,the first reception signal is generated at a TDSCDMA Band 1 filter. Ifthe second time-division signal is a TDSCDMA Band 2 signal, the firstreception signal is generated at a TDSCDMA Band 2 filter.

When the transceiver is in the frequency-division mode, a determinationis made as to whether the transceiver is in a transmission mode or areception mode at 618. When the transceiver is in the transmission mode,a first frequency-division signal (e.g., a WCDMA Band 1 uplink signal)is received at the power amplifier from the transceiver at 620. Thefirst frequency-division signal is associated with a second frequencyband (e.g., the WCDMA Band 1 uplink frequency range), where the firstfrequency band is adjacent to the second frequency band. Because thepower amplifier has a bandwidth including the first frequency band andthe second frequency band, the same amplifier is used for both branchesof the depicted process. An amplified frequency-division signal isgenerated based on the frequency-division signal at 622. A transmissionsignal is generated based on the amplified frequency-division signal ata duplexer at 624, and the transmission signal is output to the antennaswitch circuit for transmission at 626. When the transceiver is in thereception mode, a second frequency-division signal is received from theantenna switch circuit at 628. A second reception signal is generatedbased on the second frequency-division signal at the duplexer at 630,and output to the transceiver via a switch at 632.

As an example, the method depicted in FIG. 6 is implemented in thecommunication system 300 as shown in FIG. 3 for processing WCDMA Band 1signals using a duplexer and processing TDSCDMA Band 1/2 signals wherethe duplexer is bypassed.

FIG. 7 illustrates an example flow diagram depicting a method forprocessing time-division signals in a time-division mode andfrequency-division signals in a frequency-division mode using a specialduplexer. At 702, a determination is made as to whether the transceiveris in a time-division mode or a frequency-division mode. When thetransceiver is in the time-division mode, a determination is made as towhether the transceiver is in a transmission mode or a reception mode at703. When the transceiver is in the transmission mode, a firsttime-division signal (e.g., a TDSCDMA Band 1/2 signal) is received at apower amplifier from the transceiver at 704. The first time-divisionsignal is associated with a first frequency band (e.g., the TDSCDMA Band1 and Band 2), and an amplified time-division signal is generated basedon the first time-division signal at 706. For example, the amplifiedtime-division signal passes through a switch and is filtered by aduplexer. At 708, a first transmission signal is generated based on theamplified time-division signal at the duplexer that has a bandwidth thatincludes both the first frequency band and a second frequency band(e.g., the WCDMA Band 1 uplink frequency range), where the firstfrequency band is adjacent to the second frequency band. The firsttransmission signal is output to an antenna switch circuit fortransmission at 710. When the transceiver is in the reception mode, asecond time-division signal is received from the antenna switch circuitat 712. A first reception signal is generated based on the secondtime-division signal at the duplexer at 714, and is output to thetransceiver at 716 via the switch. For example, the second time-divisionsignal is filtered by the duplexer.

When the transceiver is in the frequency-division mode, a determinationis made as to whether the transceiver is in a transmission mode or areception mode at 717. When the transceiver is in the transmission mode,a first frequency-division signal (e.g., a WCDMA Band 1 uplink signal)is received at the power amplifier from the transceiver at 718. Thefirst frequency-division signal is associated with the second frequencyband. Because the power amplifier has a bandwidth that includes both thefirst frequency band and the second frequency band, the same poweramplifier can be used for both branches of the process. At 720, anamplified frequency-division signal is generated based on the firstfrequency-division signal. For example, the amplified frequency-divisionsignal passes through the switch and is filtered by the duplexer. Asecond transmission signal is generated based on the amplifiedfrequency-division signal at the duplexer at 722, and the secondtransmission signal is output to the antenna switch circuit fortransmission at 724. When the transceiver is in the reception mode, asecond frequency-division signal is received from the antenna switchcircuit at 726. A second reception signal is generated based on thesecond time-division signal at the duplexer at 728, and the secondreception signal is output to the transceiver at 730. For example, thesecond time-division signal is filtered by the duplexer.

As an example, the method depicted in FIG. 7 is implemented in thecommunication system 500 as shown in FIG. 5 for processing WCDMA Band 1signals and TDSCDMA Band 1/2 signals using a special duplexer.

Referring now to FIG. 8, an exemplary implementation of the presentinvention is shown. The present invention may be embodied in a cellularphone 802 that may include a cellular antenna 804. Processingtime-division signals and frequency-division signals according to thepresent invention may implement either or both signal processing and/orcontrol circuits, which are generally identified in FIG. 8 at 806, aWLAN interface and/or mass data storage of the cellular phone 802. Insome implementations, cellular phone 802 includes a microphone 808, anaudio output 810 such as a speaker and/or audio output jack, a display812 and/or an input device 814 such as a keypad, pointing device, voiceactuation and/or other input device. Signal processing and/or controlcircuits 806 and/or other circuits (not shown) in cellular phone 802 mayprocess data, perform coding and/or encryption, perform calculations,format data and/or perform other cellular phone functions.

Cellular phone 802 may communicate with mass data storage 816 thatstores data in a nonvolatile manner such as optical and/or magneticstorage devices for example hard disk drives HDD and/or DVDs. The HDDmay be a mini HDD that includes one or more platters having a diameterthat is smaller than approximately 1.8″. Cellular phone 802 may beconnected to memory 818 such as RAM, ROM, low latency nonvolatile memorysuch as flash memory and/or other suitable electronic data storage.Cellular phone 802 also may support connections with a WLAN via a WLANnetwork interface 820.

This written description uses examples to disclose the invention,include the best mode, and also to enable a person skilled in the art tomake and use the invention. The patentable scope of the invention mayinclude other examples that occur to those skilled in the art.

As an example, systems and methods can be configured as disclosed hereinto simplify wireless communication systems that can process bothtime-division signals and frequency-division signals. As anotherexample, systems and methods can be configured as disclosed herein toreduce the number of power amplifiers used in wireless communicationsystems. As another example, systems and methods can be configured asdisclosed herein to reduce the number of radio-frequency-signal filtersused in wireless communication systems. As another example, systems andmethods can be configured as disclosed herein to reduce layout areaneeded in wireless communication systems and save manufacturing costs.

It is claimed:
 1. A system for processing time-division signals andfrequency-division signals using a multi-mode transceiver, the systemcomprising: a power amplifier configured to receive a firsttime-division signal from the multi-mode transceiver and to generate anamplified time-division signal based on the first time-division signalwhen the multi-mode transceiver is in a time-division mode, the poweramplifier being further configured to receive a first frequency-divisionsignal from the multi-mode transceiver and to generate an amplifiedfrequency-division signal based on the first frequency-division signalwhen the multi-mode transceiver is in a frequency-division mode, thefirst time-division signal being associated with a first frequency band,the first frequency-division signal being associated with a secondfrequency band, the first frequency band being adjacent to the secondfrequency band, and the power amplifier having a bandwidth including thefirst frequency band and the second frequency band; a switchingcomponent configured to receive the amplified time-division signal fromthe power amplifier and to output the amplified time-division signal fortransmission, the switching component being further configured toreceive the amplified frequency-division signal from the power amplifierand to output the amplified frequency-division signal; and a duplexerconfigured to receive the amplified frequency-division signal from theswitching component and to output a transmission signal fortransmission; wherein the second frequency band ranges from 1920 MHz to1980 MHz, and wherein the first frequency band includes a thirdfrequency band and a fourth frequency band, the third frequency bandranging from 2010 MHz to 2025 MHz, the fourth frequency band rangingfrom 1880 MHz to 1920 MHz.
 2. The system of claim 1 wherein the firsttime-division signal is a Time Division Synchronous Code DivisionMultiple Access (TDSCDMA) signal.
 3. The system of claim 1 wherein thefirst frequency-division signal is a Wideband Code Division MultipleAccess (WCDMA) signal.
 4. The system of claim 1 wherein the poweramplifier is a TDSCDMA Band 1/2 power amplifier, a WCDMA Band 1 poweramplifier, or a power amplifier that has a bandwidth including both thefirst frequency band and the second frequency band.
 5. The system ofclaim 1, further comprising: an antenna switch circuit configured toreceive the amplified time-division signal and to receive thetransmission signal.
 6. The system of claim 5 wherein the duplexer isfurther configured to receive a second frequency-division signal fromthe antenna switch circuit and to output a first reception signal to themulti-mode transceiver, the first reception signal being generated basedon the second frequency-division signal.
 7. The system of claim 6,further comprising: a first time-division filter configured to receive asecond time-division signal from the antenna switch circuit and tooutput a second reception signal to the multi-mode transceiver, thesecond time-division signal being associated with the third frequencyband, the second reception signal being generated based on the secondtime-division signal; and a second time-division filter configured toreceive a third time-division signal from the antenna switch circuit andto output a third reception signal to the multi-mode transceiver, thethird time-division signal being associated with the fourth frequencyband, the third reception signal being generated based on the thirdtime-division signal.
 8. The system of claim 7 wherein the antennaswitch circuit includes a single pole multiple throw switch.
 9. Thesystem of claim 1 wherein the switching component is a single poledouble throw switch.
 10. The system of claim 1 wherein the duplexer hasa bandwidth including the second frequency band.
 11. The system of claim1 wherein the multi-mode transceiver supports WCDMA, TDSCDMA, and one ormore of the following standards: Code Division Multiple Access (CDMA),Global System for Mobile Communication (GSM), Enhanced Data for GSMEnvironment (EDGE), CDMA-2000, Long Term Evolution (LTE), and WorldwideInteroperability for Microwave Access (WiMAX).
 12. A system forprocessing time-division signals and frequency-division signals using amulti-mode transceiver, the system comprising: a power amplifierconfigured to receive a first time-division signal from the multi-modetransceiver and to generate an amplified time-division signal based onthe first time-division signal when the multi-mode transceiver is in atime-division mode, the power amplifier being further configured toreceive a first frequency-division signal from the multi-modetransceiver and to generate an amplified frequency-division signal basedon the first frequency-division signal when the multi-mode transceiveris in a frequency-division mode, the first time-division signal beingassociated with a first frequency band, the first frequency-divisionsignal being associated with a second frequency band, the firstfrequency band being adjacent to the second frequency band, and thepower amplifier having a bandwidth including the first frequency bandand the second frequency band; a switching component configured toreceive the amplified time-division signal or the amplifiedfrequency-division signal, and output the amplified time-division signalor the amplified frequency-division signal for further processing; and aduplexer configured to receive the amplified time-division signal or theamplified frequency-division signal from the switching component and tooutput a first transmission signal generated based on the amplifiedtime-division signal or a second transmission signal generated based onthe amplified frequency-division signal to an antenna switch circuit fortransmission, the duplexer being further configured to receive a secondtime-division signal from the antenna switch circuit and to output areception signal to the switching component, the reception signal beinggenerated based on the second time-division signal; the switchingcomponent being further configured to receive the reception signal andto output the reception signal to the multi-mode transceiver; whereinthe second frequency band ranges from 1920 MHz to 1980 MHz, and whereinthe first frequency band includes a third frequency band and a fourthfrequency band, the third frequency band ranging from 2010 MHz to 2025MHz, the fourth frequency band ranging from 1880 MHz to 1920 MHz. 13.The system of claim 12 wherein the duplexer is further configured toreceive a second frequency-division signal from the antenna switchcircuit, and to output a second reception signal to the multi-modetransceiver, the second reception signal being generated based on thesecond frequency-division signal.
 14. The system of claim 13 wherein:the duplexer includes a first port and a second port; and the duplexeris further configured to receive the second time-division signal at thefirst port from the antenna switch circuit and to receive the secondfrequency-division signal at the second port from the antenna switchcircuit.
 15. The system of claim 12 wherein the power amplifier is aTDSCDMA Band 1/2 power amplifier, a WCDMA Band 1 power amplifier, or apower amplifier that has a bandwidth including both the first frequencyband and the second frequency band.
 16. The system of claim 12 whereinthe duplexer having a bandwidth including the first frequency band andthe second frequency band.
 17. A method for processing time-divisionsignals and frequency-division signals using a multi-mode transceiver,the method comprising: (a) when the multi-mode transceiver is in atime-division mode, (i) when the multi-mode transceiver is in atransmission mode, receiving, at a power amplifier, a firsttime-division signal from the multi-mode transceiver, the firsttime-division signal being associated with a first frequency band;generating an amplified time-division signal based on the firsttime-division signal; outputting the amplified time-division signal toan antenna switch circuit for transmission; (ii) when the multi-modetransceiver is in a reception mode, receiving a second time-divisionsignal from the antenna switch circuit, the second time-division signalbeing associated with the first frequency band; generating a firstreception signal based on the second time-division signal; outputtingthe first reception signal to the multi-mode transceiver; (b) when themulti-mode transceiver is in a frequency-division mode, (i) when themulti-mode transceiver is in a transmission mode, receiving, at a poweramplifier, a first frequency-division signal from the multi-modetransceiver, the first frequency-division signal being associated with asecond frequency band, the first frequency band being adjacent to thesecond frequency band, the power amplifier having a bandwidth includingthe first frequency band and the second frequency band; generating anamplified frequency-division signal based on the firstfrequency-division signal; generating a transmission signal based on theamplified frequency-division signal at a duplexer; outputting thetransmission signal for transmission; (ii) when the multi-modetransceiver is in a reception mode, receiving a secondfrequency-division signal from the antenna switch circuit; generating asecond reception signal based on the second frequency-division signal atthe duplexer; and outputting the second reception signal to themulti-mode transceiver via a switch; wherein the second frequency bandranges from 1920 MHz to 1980 MHz, and wherein the first frequency bandincludes a third frequency band and a fourth frequency band, the thirdfrequency band ranging from 2010 MHz to 2025 MHz, the fourth frequencyband ranging from 1880 MHz to 1920 MHz.
 18. A method for processingtime-division signals and frequency-division signals using a multi-modetransceiver, the method comprising: (a) when the multi-mode transceiveris in a time-division mode, (i) when the multi-mode transceiver is in atransmission mode, receiving, at a power amplifier, a firsttime-division signal from the multi-mode transceiver, the firsttime-division signal being associated with a first frequency band;generating an amplified time-division signal based on the firsttime-division signal; generating a first transmission signal based onthe amplified time-division signal at a duplexer, the duplexer having abandwidth including the first frequency band and a second frequencyband, the first frequency band being adjacent to the second frequencyband; outputting the first transmission signal to an antenna switchcircuit for transmission; (ii) when the multi-mode transceiver is in areception mode, receiving a second time-division signal from the antennaswitch circuit; generating a first reception signal based on the secondtime-division signal at the duplexer; outputting the first receptionsignal to the multi-mode transceiver; (b) when the multi-modetransceiver is in a frequency-division mode, (i) when the multi-modetransceiver is in a transmission mode, receiving, at the poweramplifier, a first frequency-division signal from the multi-modetransceiver, the first frequency-division signal being associated withthe second frequency band, the power amplifier having a bandwidthincluding the first frequency band and the second frequency band;generating an amplified frequency-division signal based on the firstfrequency-division signal; generating a second transmission signal basedon the amplified frequency-division signal at the duplexer; outputtingthe second transmission signal to the antenna switch circuit fortransmission; (ii) when the multi-mode transceiver is in a receptionmode, receiving a second frequency-division signal from the antennaswitch circuit; generating a second reception signal based on the secondfrequency-division signal at the duplexer; and outputting the secondreception signal to the multi-mode transceiver via a switch; wherein thesecond frequency band ranges from 1920 MHz to 1980 MHz, and wherein thefirst frequency band includes a third frequency band and a fourthfrequency band, the third frequency band ranging from 2010 MHz to 2025MHz, the fourth frequency band ranging from 1880 MHz to 1920 MHz.